Connection reset by peer) while reading response header from upstream

[Siava <siava@xxxxxxxx>]

Добрый день.
Nginx использую для отдачи статики.
На днях обновил свой Slackware с 11 до 12 версии, перекомпилировал nginx 
и тут же, с первого дня в error.log посыпались переодические ошибки 
такого вида:
2007/07/17 20:42:00 [error] 7185#0: *141070 recv() failed (104: 
Connection reset by peer) while reading response header from upstream, 
client: 74.6.87.23, server: siava.ru, URL: "/forum/topic2654.html",

upstream: "http://127.0.0.1:5005/forum/topic2654.html";, host: "siava.ru"

2007/07/17 20:42:00 [error] 7183#0: *141012 recv() failed (104: 
Connection reset by peer) while reading response header from upstream, 
client: 213.158.12.37, server: siava.ru, URL: 
"/forum/album_thumbnail.php?pic_id=15", upstream:

"http://127.0.0.1:5005/forum/album_thumbnail.php?pic_id=15";, host:

"siava.ru", referrer: "http://siava.ru/forum/";

.....

Не понимаю откуда они берутся, пробовал менять конфиг (увеличил 
keepalive_timeout с 0 до 30, не помогло) , кстати, прилагаю его:
user  nobody;
worker_processes  4;

events {
   worker_connections  1024;
}


http {
   include    conf/mime.types;
   default_type    application/octet-stream;

   log_format  main    '$remote_addr - $remote_user [$time_local] 
$request '

               '"$status" $body_bytes_sent "$http_referer" '
               '"$http_user_agent" "$http_x_forwarded_for" ';

   access_log  logs/access.log  main;

   sendfile        on;
   tcp_nopush        on;
   tcp_nodelay        on;

   keepalive_timeout    30;

   server {
   listen            80;
   server_name        siava.ru    max_fails=2    fail_timeout=20s;

   access_log        off;
   log_not_found        off;

       location / {
       proxy_pass        http://127.0.0.1:5005/;
       proxy_redirect        off;

       proxy_set_header    Host            $host;
       proxy_set_header    X-Real-IP        $remote_addr;
       proxy_set_header    X-Forwarded-For    $proxy_add_x_forwarded_for;

       client_max_body_size        250m;
       client_body_buffer_size        128k;

       proxy_connect_timeout        20;
       proxy_send_timeout        60;
       proxy_read_timeout        300;

       proxy_buffering            on;
       proxy_buffer_size        16k;
       proxy_buffers            4 32k;
       proxy_busy_buffers_size        64k;
       proxy_temp_file_write_size    64k;
       }

       location ~* 
^.+\.(jpg|jpeg|gif|png|ico|css|zip|tgz|gz|rar|bz2|doc|xls|exe|pdf|ppt|tar|wav|bmp|rtf|js)$ 
{
           root /usr/local/www/siava.spb.ru;
           expires      30d;
       }
  
       error_page   500 502 503 504  /50x.html;

       location = /50x.html {
           root   html;
       }
   }

}

--
Siava
WEB http://siava.ru